I have the 8 ohm version (circa 1969) that I repaired to good working condition. Build quality is excellent, and I think the cabinets are solid walnut. They probably weigh 50-60 lbs each. Woofer sag is apparently pretty common but was easily fixable in my case. I rotated the woofers 180 degrees in the cabinets and adjusted the magnets to solve voice coil rub. I also recapped them and made adapters for the proprietary terminals.
They sound better than I had expected. Good mids and nice, tight bass. They are lacking somewhat in the very high frequencies, but still very enjoyable - especially for jazz music. I had never researched the specs, but they seem pretty efficient too. I wouldn't sell my pair in excellent shape for under $200.
